Phosphole and diphosphole ligands for catalysis

ABSTRACT

Novel reactions used to prepare phosphole and bisphosphole compounds are detailed. Novel phosphole compounds and metal coordination compounds of phosphole and bisphosphole compounds are also provided. These metal coordination compounds are useful as catalysts for the polymerization or olefins with carbon monoxide and for the polymerization of acrylic monomers.

This is a division of application Ser. No. 09/415,388 filed Oct. 8, 1999, now U.S. Pat. No. 6,137,012 which application claims benefit of Provisional Application No. 60/104,112, filed Oct. 13, 1998.

FIELD OF INVENTION

The invention relates to new phosphole and diphosphole based ligands useful as polymerization catalysts.

BACKGROUND

The phosphole ring system is described by structure A. This structure is distinct from the class of compounds B which contain benzo rings fused to the phosphole core.

Class I has a much different electronic structure and therefore has much different chemistry than compounds of class II. In class I, the P atom is part of the delocalized, partally aromatic ring system. In class II, the aromaticity is confined to the benzo rings, with no delocaliaion around the P atom. Class I will participate in Diels-Alder chemistry (especially when complexed to a metal) (Bhaduri et al., Organometallics 1992, 11, pp. 4069-4076), whereas compounds of class II will not (Quin, Compr. Heterocycl. Chem. II Bird, Clive W (Ed), 1996, Vol. 2, pp. 757-856).

Very few compounds have been reported that contain two phosphole rings connected via a bridge (A) between the phosphorus atoms (structure C) (A=bridging hydrocarbon, hydrocarbon/heteroatom(s), or organometallic group).

One explanation for the paucity of compounds of type C-G is the lack of synthetic procedures broad enough in scope to prepare the phosphole ring system.

Examples reported in the literature include the compounds 1 (Braye et al., Tetrahedron 1971, pp. 5523-37), 2 (A=—CH₂—, —CH₂CH₂—, and —CH═CH—CH═CH—) (Charrier et al., Organometallics 1987, 6 pp. 586 91), and 3 (Gradoz et al., J. Chem. Soc. Dalton Trans. 1992, pp. 3047-3051).

Compounds containing a single phosphole ring (I) were made using the Fagan-Nugent heterocycle synthesis (Fagan et al., J. Am. Chem. Soc. 1994, 116, pp. 1880-1889; Fagan et al., J. Am. Chem. Soc. 1988, 110, pp. 2310-2312). This synthesis involves preparing the zirconium reagents by coupling of acetylenes followed by transfer of the metallacycle from zirconium to phosphorus. In all cases, the substituent on the phosphorus was an aromatic group such as phenyl.

These types of compounds (containing a single phosphole ring) have found limited utility as ligands for transition metals for use in catalysis, and have been shown to have different chemistries than their phosphine analogs (Neibecker et al., New J. Chem. 1991, pp. 279-81; Neibecker et al., J. Mol. Catal. 1989, 57 pp. 153-163; Neibecker et al., J. Mol. Catal. 1989, 219-227; Vac et al., Inorg. Chem. 1989 28, pp. 3831-3836; Hjortkjaer et al., J. Mol. Catal. 1989 50, 203-210).

Transition metal complexes have been made using structures of class VII, shown below, where the rings are linked at the position alpha to phosphorus. Attempts to use these ligands to make Pd acetonitrile complexes analogous to those in the instant invention failed (Guoygou et al., Organometallics 1997, 16, 1008-1015).

Copolymers of carbon monoxide and olefins, such as ethylene, can be made by free radical initiated copolymerizaton (Brubaker, J. Am. Chem. Soc., 1952, 74, 1509) or gamma-ray induced copolymerization (Steinberg, Polym. Eng. Sci., 1977, 17, 335). The copolymers produced were random copolymers and their melting points were low. In 1951, Reppe discovered a nickel-catalyzed ethylene carbon monoxide copolymerization system that gave alternating copolymers (U.S. Pat. No. 2,577,208 (1951)). However, the molecular weights of these polymers were also low.

In 1984, U.S. Pat. Nos. 4,818,810 and 4,835,250 disclosed the production of alternating olefin carbon monoxide copolymers based on Pd(II), Ni(II) and Co(II) complexes bearing bidentate ligands of the formula R₁R₂E—A—E—R₃R₄, wherein R₁, R₂, R₃, R₄, and A are organic groups and E is phosphorus, arsenic, or antimony. When E is phosphorus and R₁₋₄ are aryl groups, the corresponding diphosphine palladium complexes are active in copolymerizing ethylene and carbon monoxide to produce copolymers of molecular weight up to 30,000 (MW_(n)) (Drent et al., Chem. Rev., 1996, 96, 663). No compounds were claimed or disclosed in which R₁ and R₂, and R₃ and R₄ together formed a ring. Applicants have recently found that the diphosphole coordinated palladium catalysts catalyze olefin/carbon monoxide (CO) copolymerization. When the P atom is part of a ring system, the electronic environment and therefore expected chemistries are different than simple, non-ring phosphine disclosed in the patents described above.

Radical polymerization is an important commercial process for making a variety of polymers of vinyl monomers, such as acrylics and styrenics. While this process makes large amounts of polymers, the difficulty in accurately controlling the polymer stuctures (such as molecular weight, molecular weight distribution, and architecture, etc.) has significantly limited its further applications.

Living polymerizaton usually offers much better control on polymer structures and architectures. While living polymerization systems for anionic, cationic, and group transfer mechanisms were developed some years ago, a true living radical polymerization system is still an elusive goal (because of the high reactivity of free radicals) and only very recently has pseudo-living radical polymerization been achieved. One pseudo-living radical polymerization method is “atom transfer radical polymerization” (ATRP). In this process a transition metal compound, usually in a lower valent state, is contacted with a compound which is capable of transferring an atom to the metal complex, thereby oxidizing the metal to a higher valent state and forming a radical which can initiate polymerization. However, the atom that was transferred to the metal complex may be reversibly transferred back to the growing polymer chain at any time. In this way, the propagation step is regulated by this reversible atom transfer equilibrium and statistically all polymer chains grow at the same rate. The results a pseudo-living radical polymerization in which the molecular weight may be closely controlled and the molecular weight distribution is narrow.

Such ATRPs are described in many publications (Kato et al., Macromolecules 1995, 28, 1721; Wang et al., Macromolecules 1995, 28, 7572; Wang et al., Macromolecules 1995, 28, 7901; Granel et al., Macromolecules 1996, 29, 8576; Matyjaszewski et al., PCT WO 96/30421). The transition metal complexes used include complexes of Cu(I), Ru(II), Ni(II), Fe(II), and Rh(II). The complexes are formed by coordinating the metal ions with certain ligands such as nitrogen or phosphine containing ligands. For Ru(II) and Fe(II), mono-phosphine P(C₆H₅)₃ was used as the ligand. However, for Cu(I), all the ligands used are nitrogen-based such as bipyridine or substituted bipyridine. No phosphine-based ligand has been shown to be an effective ligand for Cu(I) in ATRP.

It has been found that novel types of ligands containing phosphole and other P ring systems can chelate Cu(I) to form active catalysts for ATRP.

SUMMARY OF THE INVENTION

An object of this invention is to provide a process for the preparation of compounds of formulae I and II

by reacting a compound of formula X₂P—A—PX₂ (III) with a compound of formula IV;

wherein R₁, R₂, R₃ and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₂ and R₃ together can optionally form a ring; Cp is cyclopentadienyl; X is selected from the group consisting of Cl, Br, and I; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferably A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, wherein R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. More preferably R₁, R₂, R₃ and R₄ are alkyl groups.

The invention also provides for a compound of the formula

wherein R₁, R₂, R₃ and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O and S; R₂ and R₃ together and R₅ and R₆ together can optionally form a ring; Cp is cyclopentadienyl (η⁵-C₅H₅); A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferably A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, wherein R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. More preferably R₁, R₂, R₃ and R₄ are alkyl groups and R₅ and R₆ are selected from the group consisting of alkyl groups and Cl.

A further object of the invention is a coordination compound comprising one or more transition metals complexed to one or more of the following compounds as ligands:

wherein R₁, R₂, R₃ and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O and S; R₂ and R₃ together and R₅ and R₆ together can optionally form a ring; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferably the transition metal is Pd and A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, wherein R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. More preferably R₁, R₂, R₃, and R₄ are alkyl groups and R₅ and R₆ are selected from the group consisting of alkyl groups and Cl.

The invention also provides a process for the preparation of a polyketone by contacting a mixture of carbon monoxide with one or more alkenes under polymerization conditions with a catalyst comprising a transition metal complexed with one or more ligands of the formulae IIA or VA

wherein the rings are optionally-substituted and are optionally members of a larger bicyclic or tricyclic ring system; each P atom is bonded to only three other atoms in the ligand; the two atoms in the ring adjacent to the P atom are C atoms; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O, and S; R₅ and R₆ together can optionally form a ring; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferably the transition metal is Pd and the ligand is of the formulae V or II

wherein R, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O, and S; R₂ and R₃ together and R₅ and R₆ together can optionally form a ring; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. More preferably A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl R₁, R₂, R₃, and R₄ are alkyl groups, R₅ and R₆ are selected from the group consisting of alkyl groups and Cl, and the alkene is ethylene.

Another object of the invention is a process for the polymerization of an acrylic monomer by contacting at least one acrylic monomer under polymerization conditions with a catalyst comprising Cu(I) complexed with one or more ligands of the formulae IIA or VA

wherein the rings are optionally-substituted and are optionally members of a larger bicyclic or tricyclic ring system; each P atom is bonded to only three other atoms in the ligand; the two atoms in the ring adjacent to the P atom are C atoms; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O, and S; R₅ and R₆ together can optionally form a ring; A is a divalent group of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferably the ligand is of the formulae V or II

wherein R₁, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O, and S; R₂ and R₃ together and R₅ and R₆ together can optionally form a ring; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl. More preferably A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, wherein R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl and substituted hydrocarbyl, R₁, R₂, R₃, and R₄ re alkyl groups, R₅ and R₆ are selected from the group consisting of alkyl groups and Cl, and the acrylic monomer is methylmethacrylate.

DETAILED DESCRIPTION OF THE INVENTION

This invention provides novel reactions used to prepare phosphole and bisphosphole compounds. Novel phosphole compounds and metal coordination compounds of phosphole and bisphosphole compounds are also provided. These metal coordination compounds are useful as polymerization catalysts.

The present invention provides processes for the preparation of bisphosphole compounds of formulae I and II

by reacting a compound of formula IV with a compound of formula X₂P—A—PX₂ (III);

wherein:

R₁, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl;

R₂ and R₃ together can optionally form a ring;

Cp is cyclopentadienyl (η⁵-C₅H₅);

X is selected from the group consisting of Cl, Br, and I;

A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and

R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

By hydrocarbyl is meant a straight chain, branched or cyclic arrangement of carbon atoms connected by single, double, or triple carbon to carbon bonds and/or by ether linkages, and substituted accordingly with hydrogen atoms. Such hydrocarbyl groups may be aliphatic and/or aromatic. Examples of hydrocarbyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopentyl, cyclohexyl, methylcyclohexyl, benzyl, phenyl, o-tolyl, m-tolyl, p-tolyl, xylyl, vinyl, allyl, butenyl, cyclohexenyl, cyclooctenyl, cyclooctadienyl, and butynyl. Examples of substituted hydrocarbyl groups include toluyl, chlorobenzyl, fluoroethyl, p-CH₃—S—C₆H₅, 2-methoxy-propyl, and (CH₃)₃SiCH₂.

“Coordination compound” refers to a compound formed by the union of a metal ion (usually a transition metal) with a non-metallic ion or molecule called a ligand or complexing agent.

Preferred compounds of formulae II and I include those where A is selected from the group consisting of —N(R₇)—N(R₈)— and carbon chains of 1-3 carbons. Also preferred are compounds of formulae III and IV where R₁, R₂, R₃, and R₄ are alkyl groups. Most preferred are 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane; 1,2-bis(2,3,4,5-tetraethylphospholyl)ethane; 1,1-bis(2,3,4,5-tetramethylphospholyl)methane; 1,1-bis(2,3,4,5-tetraethylphospholyl)methane; 1,2-bis(2,3,4,5-tetraethylphospholyl)-1,2-dimethylhydrazine; 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane; and 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane-1,2-dimethylhydrazine.

The process can be run in a wide variety of solvents. Preferred solvents are CH₂Cl₂ and THF (tetrahydrofuran). Low temperatures, below from about −100° C. to room temperature, are typically used.

The zirconium reagents (IV) are first prepared by reacting Cp₂ZrCl₂ (Cp═η⁵-C₅H₅, cyclopentadienyl) with n-BuLi at about −78° C. followed by warming in the presence of an alkyne, alkynes, or dialkyne. The metallacycles can be isolated, or used in situ. When these are reacted with one-half of a molar equivalent of a diphosphorus compound X₂P—A—PX₂, compounds of formula II result (Scheme 1).

If zirconium metallacycles of type IV are reacted with at least one equivalent of the phosphorus reagents X₂P—A—PX₂, then compounds of formula I can be prepared (Scheme 2).

Dialkynes provide zirconium metallacycles of formula IVA which can be reacted with X₂P—A—PX₂ to form compounds of formula II wherein R₂ and R₃ together form a ring as illustrated in Scheme 3.

where Z is any linking group with proper orientation or is flexible enough to allow the reaction to proceed. Examples of suitable linking groups include hydrocarbyl, substituted hydrocarbyl, and organometallic compounds. Preferred is —(CH₂)_(x)—, where X is 1-10.

The above reactions should be performed under a N₂ atmosphere using anhydrous solvents.

Similarly, the products from reaction of zirconium metallacycles IVA allows the corresponding compounds of formula I wherein R₂ and R₃ together form a ring to be prepared (Scheme 4).

The present invention also provides for novel phosphole compositions of the formula V

wherein

R₁, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl;

R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O, and S;

R₂ and R₃ together and R₅ and R₆ together can optionally form a ring;

A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and

R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

Preferred compounds of formulae V include those where A is selected from the group consisting of —N(R₇)—N(R₈)— and carbon chains of 1-3 carbons. Also preferred are compounds of formulae V where R₁, R₂, R₃, and R₄ are alkyl groups, and where R₅ and R₆ are hydrocarbyl, substituted hydrocarbyl, alkoxy, Cl, Br, and I. Most preferred are 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane-1,2-dimethylhydrazine; [2-(tetramethylphospholyl)ethyl]-[(R,R)-2,7-dimethyl-3,6-decadiyl]phosphine; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-chlorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-tert-butylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-diethynylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(n-propynyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-fluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(phenylethynyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-divinylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-dicyclopentylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(n-decyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-fluoro-3-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3,4-difluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-butylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-fluoro-2-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2-naphthyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methylthiophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-methoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-fluoro-4-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2-methoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-phenoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-[4-(dimethylamino)phenyl]phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2,4-difluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2,4,6-trimethylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-isopropenylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-diallylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-trimethylsilylmethylphosphinoethane; and 1-(2,3,4,5-tetramethylphospholyl)-2-di-[2-[1,3]dioxan-2-ylethyl]phosphinoethane.

Compounds of formula V where X is Cl, Br, or I can be prepared as detailed above. Other compounds of formula V can be prepared using compounds of formula I as an intermediate (Scheme 6).

wherein

R₁, R₂, R₃, R₄, R₅, R₆, R₇, R₈, A, and Z are as defined above,

R₉ and R₁₀ are selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl;

M is any metal; and

R₂ and R₃ together and R₅ and R₆ together can optionally form a ring.

An alternative route to compounds of formula V and other compounds is the synthetic sequence shown in Scheme 7.

Alternate syntheses can be used to prepare bis(phosphole) compounds of formulae II from compounds previously detailed above (Scheme 8).

Another aspect of the present invention provides for novel coordination compounds comprising one or more transition metals complexed to one or more compounds of formulae V or II

wherein

R₁, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl;

R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, N, O and S;

R₂ and R₃ together and R₅ and R₆ together can optionally form a ring;

A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and

R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.

The transition metals are hereby defined as metals of atomic weight 21 through 83. Preferred metals are those of Cu(I) or of Periodic Group VIII, hereby defined as Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt. Most preferred is Pd.

Reactions to form coordination compounds use either a well-defined palladium catalyst such as [(diphosphole)PdMe(CH₃CN)]SbF₆ or catalysts generated in situ by mixing the diphospole ligand with palladium salts such as [Pd(CH₃CN)₄](BF₄)₂ or Pd(OAc)₂. Catalysts prepared in situ were made from 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane and Pd(OAc)₂ and from 1,3-bis(2,3,4,5-tetramethylphospholyl)propane and [Pd(CH₃CN)₄(BF₄)₂. Preferred coordination compounds are [1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMeCl; {[1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMe(CH₃CN)}SbF₆; [1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine]PdMeCl; and {[1,2-bis(2,3,4,5-tetramethylphospholyl)-1, 2-dimethylhydrazine]PdMe(CH₃CN)}SbF₆.

Coordination compounds made in the instant invention can be used as catalysts for olefin/carbon monoxide polymerizations. The olefin can be an alkene or a cycloalkene containing 2-30, preferably 2-12, carbon atoms. Examples of suitable alkenes can include ethylene, propylene, any isomeric butene, pentene, hexene, octene, and dodecene, cyclooctene, cyclododecene, styrene, methylstryene, acyrlic acid, methacrylic acid, alkyl esters of acrylic and metacylic acids, and dialkenes in which the two unsaturated groups are not conjugated.

Any suitable method to prepare polymer from carbon monoxide and an olefin using the instant catalysts can be used. The catalysts themselves can be isolated before polymerization or generated in situ. Preferred catalysts for this process contain Pd.

The ligands made in the instant invention can also be used to prepare Cu(I) coordination compounds, which are useful as catalysts in ATRP (atom transfer radical polymerization) processes, as defined above, to polymeric acrylic monomers. The acrylic monomers are of the formula

where R₁ is hydrogen, alkyl, or substituted alkyl group, and R₂ is hydrogen, hydrocarbyl or substituted hydrocarbyl. Preferred are compounds where R₁ is hydrogen, methyl or ethyl and R₂ is hydrogen or methyl. Most preferred is where R₁ and R₂ are both methyl (methylmethacrylate).

Any suitable method to prepare the acrylic polymers using the instant catalysts can be used. The catalysts themselves can be isolated before polymerization or generated in situ. Preferred catalysts are those formed in situ from 1,2-bis(2,3,4,5-tetramethylphospholyl)-ethane and CuCl.

Materials and Methods

The following non-limiting Examples are meant to illustrate the invention but are not intended to limit it in any way.

Abbreviations used hereafter are listed and defined below as follows:

DSC—Differential scanning calorimetry

GPC—Gel Permeation chromatography

HFIP—1,1,1,3,3,3-Hexafluoroisopropanol

COD—1,5-Cyclooctadiene

FID—Flame ionization detection

ATRP—Atom transfer radical polymerization

MMA—Methyl methacylate

ECO—Ethylene/carbon monoxide

All manipulations of air-sensitive materials were carried out with rigorous exclusion of oxygen and moisture in flame-dried Schlenk-type glassware on a dual manifold Schlenk line, interfaced to a high-vacuum (10⁻⁴-10⁻⁵ Torr) line, or in a nitrogen-filled Vacuum Atmospheres glovebox with a high-capacity recirculator (1-2 ppm of O₂). Before use, all solvents were distilled under dry nitrogen over appropriate drying agents (sodium benzophenone ketyl, metal hydrides except for chlorinated solvents). Deuterium oxide and chloroform-d were purchased from Cambridge Isotopes (Andover, Mass.). All organic starting materials were purchased from Aldrich Chemical Co., Farchan Laboratories Inc. (Kennett Square, Pa.), or Lancaster Synthesis Inc. (Windham, N.H.), and when arrropriate were distilled prior to use. The substrate zirconium metallacycle (η⁵-C₅H₅)₂ZrC₄Me₄, 2,3,4,5-tetramethylphospholylchloride were synthesized according to literature procedures. The substrates zirconium metallacycles (η⁵-C₅H₅)₂ZrC₄Et₄, (η⁵-C₅H₅)₂Zr(Me₃C—CCCH₂CH₂CH₂CC—CMe₃), and, 2,3,4,5-tetraethylphospholylchloride, 1,7-ditertbutyl-1,6-bicyclo[3,3]heptadiynyl-phospholylchloride were synthesized via modifications of literature methods as described below.

Physical and Analytical Measurements

NMR spectra were recorded on either a Nicolet NMC-300 wide-bore (FT, 300 MHz, ¹H; 75 MHz, ¹³C, 121 MHz ³¹P), or GE QM-300 narrow-bore (FT, 300 MHz, ¹H) instrument. Chemical shifts (δ) for ¹H, ¹³C are referenced to internal solvent resonances and reported relative to SiMe₄. ³¹P NMR shifts are reported relative to external phosphoric acid. Analytical gas chromatography was performed on a Varian Model 3700 gas chromatograph with FID detectors and a Hewlett-Packard 3390A digital recorder/integrator using a 0.125 in. i.d. column with 3.8% w/w SE-30 liquid phase on Chromosorb W support. GC/MS studies were conducted on a VG 70-250 SE instrument with 70 eV electron impact ionization. Melting points and boiling points are uncorrected.

EXAMPLES

The following Examples are meant to illustrate embodiments of the invention, but are not intended to limit its scope to the named elements.

Example 1

Synthesis of 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane

Method A

A solution of Cp₂ZrC₄Me₄ (2.76 g, 8.47 mmol) in CH₂Cl₂ (60 mL) was added dropwise to a stirring solution of 1,2-bis(dichlorophosphino)ethane (0.97 g, 4.2 mmol) in CH₂Cl₂ (10 mL) at room temperature over a period of 10 min, and the resulting reaction mixture was stirred for an additional 10 min before removal of the solvent under vacuum. The residue was extracted with pentane (3×70 mL) and filtered. The filtrate was dried under vacuum, and then sublimated at 130° C./10⁴ Torr to afford 1.0 g (78% yield) of (C₄Me₄P)CH₂CH₂(PC₄Me₄).

¹H NMR (300 MHz, CD₂Cl₂): δ1.94 (s, 12H, 4Me), 1.91 (s, 12H, 4Me), 1.33 (s, 4H, 2CH₂). ¹³C NMR (75 MHz, CD₂Cl₂): δ143.8 (d, Jp-c=9.8 Hz), 133.2 (s), 17.0 (d, Jp-c=23.0 Hz), 14.0 (s), 13.1 (d, Jp-c=21.8 Hz). ³¹P NMR (122 MHz, CD₂Cl₂): δ16.1 (s). Anal. Calcd for C₁₈H₂₈P₂: C, 70.57; H, 9.21; P, 20.22. Found: C, 70.58; H, 9.02; P, 20.23.

Example 2

Method B

A mixture of Cp₂ZrCl₂ (27.0 g, 92.5 mmol) and 2-butyne (16.0 mL, 204 mmol) in THF (150 mL) was treated dropwise with n-butyllithium (186 mmol, 1.6 M solution in hexane) at −78° C. for 10 min. The resulting reaction suspension was then allowed to stir at room temperature for 2.5 hr before cooling to 78° C. 1,2-bis(dichlorophosphino)ethane (10.7 g, 46.3 mmol) was added, the mixture was warmed to room temperature and stirred for 30 min before removal of the solvent under vacuum. The residue was extracted with pentane (3×100 mL) and filtered. The filtrate was dried under vacuum, and then sublimated at 130° C./10⁴ Torr to afford 9.9 g (70% yield) of (C₄Me₄P)CH₂CH₂(PC₄Me₄).

Example 3

Synthesis of 1,2-bis(2,3,4,5-tetraethylphospholyl)ethane

A procedure similar to that described above for 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane (Method A) above was used in synthesis of the title compound yielding 5.0 g (92% yield).

¹H NMR (300 MHz, C₆D₆): δ2.53 (m, 4H), 2.27 (m, 12H), 1.65 (t, J=5.7 Hz, 4H), 1.18 (t, J=7.2 Hz, 12H), 0.99 (t, J=7.5 Hz, 12H). ¹³C NMR (75 MHz, C₆D₆): δ148.7, 142.1, 22.0 (d, Jp-c=19.4 Hz), 21.0, 17.8 (d, Jp-c=25.5 Hz), 17.1 (d, Jp-c=8.5 Hz), 15.4. ³¹P NMR (122 MHz, C⁶D₆): δ4 (s). MS (rel. abundance): M⁺(33), M⁺−Me(60), M⁺−Et(15), 223.2(6), 195.1(26), 167.1(14). High-resolution mass spectrum: Calcd for C₂₆H₄₄P₂ (M⁺): 418.2918. Found: 418.2924. Anal. Calcd for C₂₆H₄₄P₂: C, 70.57; H, 9.21; P, 20.22. Found: C, 74.14; H, 10.70; P, XX.

Example 4

The procedure was the same as described above for 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane (Method B). The product, (C₄Et₄P)CH₂CH₂(PC₄Et₄), was isolated in 65% yield.

Example 5

Synthesis of 1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine

A solution of Cp₂ZrCl₂ (6.67 g, 20.0 mmol) and Cl₂PN(Me)N(Me)PCl₂ (2.3 g, 8.6 mmol) in CH₂Cl₂ (150 mL) was refluxed overnight before removal of the solvent. The resulting residue was extracted with 3×100 mL of hexane. After removal of the hexane, the residue was sublimated at 170° C./10⁻⁵ Torr, and then recrystallized from hexane to afford 2.67 g (92% yield) of title compound.

¹H NMR (300 MHz, CD₂Cl₂): δ2.60 (d, J_(P-H)=3.9 Hz, 6H, 2Me—N), 2.00 (d, J_(P-H)=9.9 Hz, 12H, 4Me), 1.84 (d, J_(P-H)=2.7 Hz, 12H, 4Me). ¹³C NMR (75 MHz, CD₂Cl₂): δ140.2 (d, Jp-c=15.9 Hz), 132.4 (s), 39.4 (s), 13.1 (s), 12.8 (d, Jp-c=3.6 Hz). ³¹P NMR (122 MHz, CD₂Cl₂): δ77.2 (s). MS (rel. abundance): M⁺(61), M⁺−Me(2), 278.1(15), 197.1(31), 168.1(100), 139.1 (62). High-resolution mass spectrum: Calcd for C₁₈H₃₀N₂P₂ (M⁺): 336.1884. Found: 336.1881.

Example 6

Synthesis of 1,1-bis(2,3,4,5-tetramethylphospholyl)methane

A procedure similar to that described above for 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane (Method A) was used in synthesis of the title compound yielding 1.30 g (97% yield).

¹H NMR (300 MHz, C₆D₆): δ2.06 (m, 14H), 1.74 (s, 12H). ¹³C NMR (125.7 MHz, C₆D₆): δ142.8, 136.7, 19.3 (t, Jp-c=31.9 Hz), 14.1, 14.0 (t, Jp-c=12.9 Hz). ³¹P NMR (122 MHz, C₆D₆): δ4.3. MS (rel. abundance): M⁺(96), M⁺+H(100), M⁺−H(30), 153(54). High-resolution mass spectrum: Calcd for C₁₇H₂₆P₂ (M⁺): 292.1510. Found: 292.1513.

Example 7

Synthesis of 1,1-bis(2,3,4,5-tetraethylphospholyl)methane

A procedure similar to that described above for 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane (Method A) above was used in synthesis of the title compound (1.70 g, 92% yield).

¹H NMR (300 MHz, C₆D₆): δ1.02 (t, J=7.6 Hz, 12H), 1.25 (t, J=7.5 Hz, 12H), 2.29 (m, 8H), 2.56 (m, 10H). ¹³C NMR (125.7 MHz, C₆D₆): δ149.0, 147.5, 23.8 (t, Jp-c=10.8 Hz), 22.7, 19.5, 17.1. ³¹P NMR (122 MHz, C₆D₆): δ−8.1. MS (rel. abundance): M⁺(33), M⁺−H(7), M⁺−Me(7), M⁺−Et(17), 209.1(100), 195.1(22), 181.1(19), 167.198). High-resolution mass spectrum: Calcd for C₂₅H₄₂P₂ (M⁺): 404.2762. Found: 404.2777.

Example 8

Synthesis of 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophospinoethane

A solution of Cl₂PCH₂CH₂PCl₂ (4.0 g, 16.9 mmol) in CH₂Cl₂ (70 mL) was treated dropwise with a solution of Cp₂ZrC₄Me₄ (5.6 g, 16.9 mmol) in CH₂Cl₂ (50 mL) at −39° C. over a period of 3 hr. The resulting reaction mixture was then slowly warmed to room temperature and stirred overnight before removal of the solvent. The residues were extracted with hexane (3×100 mL) and the extracts were concentrated to give 4.1 g (90% yield) of colorless oil.

¹H NMR (300 MHz, C₆D₆): δ1.90 (m, 2H), 1.79 (d, J=10.5 Hz, 6H), 1.63 (s, 6H), 1.59 (m, 2H). ¹³C NMR (75 MHz, C₆D₆): δ144.8, 133.0, 37.7 (d, Jp-c=48.8 Hz), 15.2 (dd, J=9.8 Hz), 13.9, 13.0 (d, J=22.0 Hz). ³¹P NMR (122 MHz, C₆D₆): δ197.7, 11.4. MS (rel. abundance): M⁺(18), 232.0(100), 204.0(30), 138.0(82), 123.0(40), 91.1(26). High-resolution mass spectrum: Calcd for C₁₀H₁₆Cl₂P₂ (M⁺): 268.0104. Found: 268.0101.

Example 9

Synthesis of 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophospino-1,2-dimethylhydrazine

A procedure analogous to that described above for 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophospinoethane was used in the synthesis of this diphosphine derivative with Cp₂ZrC₄Me₄ (6.2 g, 18.78 mmol) and Cl₂PN(Me)N(Me)PCl₂ (5.0 g, 18.7 mmol) at room temperature. The NMR yield (˜90%) was estimated by the ¹H and ³¹P NMR.

¹H NMR (300 MHz, CD₂Cl₂): δ3.07 (d, J_(P-H)=5.1 Hz, 3H, Me—NPCl₂), 2.65 (dd, J_(P-H)=1.5 Hz, 3H, MeNNPCl₂), 2.00 (d, J_(P-H)=10.5 Hz, 6H, 2Me), 1.85 (d, J_(P-H)=3.3 Hz, 6H, 2Me). ¹³C NMR (75 MHz, CD₂Cl₂): δ143.4 (d, Jp-c=16.9 Hz), 131.2 (s), 39.7 (s), 33.7 (d, Jp-c=6.1 Hz), 13.9 (d, Jp-c=2.4 Hz), 13.0 (d, Jp-c=21.8 Hz). ³¹P NMR (122 MHz, CD₂Cl₂): δ153.3 (d, Jp-p=12.8 Hz), 82.9 (d, Jp-p=14.9 Hz). MS (rel. abundance): M⁺−HCl(24), 227.1(29), 196.0(20), 167.1(90), 137.0(94), 60.0(100), 232.0(100), 204.0(30), 138.0(82), 123.0(40), 91.1(26). High-resolution mass spectrum: Calcd for C₁₀H₁₇N₂P₂Cl (M⁺−HCl): 262.0556. Found: 262.0558.

Example 10

Synthesis of 1,3-bis(2,3,4,5-tetraethylphospholyl)propane

Synthesis of (2,3,4,5-tetramethylphospholyl)lithium

To a solution of 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane prepared as described in Example 1, Method A, 5.0 g (16.3 mmol) in THF (70 mL) at room temperature was added clean Li ribbon (1.0 g, 144.0 mmol) under Ar. The reaction mixture was allowed to stir overnight before filtering out the excess Li. The filtrate was dried in vacuum to afford 4.7 g (99% yield) of title compound. Reduction of the ethano-bridged diphosphole ligand resulted in removal of the bridge (presumably as ethylene) and formation of the tetramethylphospholyl anion. The NMR data agree with literature data (Douglas et al., 1989, Angew. Chem. Int. Ed. Engl. 28 (10), 1367-7.)

Synthesis of (2,3,4,5-tetraethylphospholyl)lithium

A procedure similar to that for (2,3,4,5-tetramethylphospholyl)lithium described above was used in synthesis of the title compound using 1,1-bis(2,3,4,5-tetraethylphospholyl)methane from Example 7 as the starting material (1.23 g, 98% yield).

¹H NMR (300 MHz, THF-d₈): δ2.54 (t, J=7.9 Hz, 4H), 2.37 (d, J=7.2 Hz, 4H), 1.14 (m, 6H, 0.96 (m, 6H). ³¹P NMR (122 MHz, THF-d₈): δ56.0.

A suspension of Li C₄Et₄P (1.75 g, 8.67 mmol) in THF (80 mL) was treated dropwise with BrCH₂CH₂CH₂Br (0.88 g, 4.34 mmol) at −30° C. for 10 min. The resulting reaction mixture was then warmed to room temperature and refluxed overnight. The solution was cooled to room temperature and quenched with CH₃OH (3.0 mL). After removal of the solvents, the residue was extracted with 3×50 mL of hexane. The combined hexane extracts were dried under reduced pressure to give 0.81 g (44% yield) of (C₄Et₄P)CH₂CH₂CH₂(PC₄Et₄).

¹H NMR (300 MHz, C₆D₆): δ2.50 (m, 4H), 2.25 (m, 14H), 1.68 (m, 4H), 1.19 (t, J=7.2 Hz, 12H), 0.99 (t, J=7.2 Hz, 12H). ¹³C NMR (75 MHz, C₆D₆): δ147.9, 142.9, 25.4 (d, Jp-c=17.1 Hz), 22.0 (d, Jp-c=18.3 Hz), 21.5, 21.1, 17.4, 15.6. ³¹P NMR (122 MHz, C₆D₆): δ2.38. MS (rel. abundance): M⁺(17), M⁺−Et(100), 237.2(60). High resolution mass spectrum: Calcd for C₂₇H₄₆P₂ (M⁺): 432.3075. Found: 432.3094.

Examples 11-40

Reaction With Grignards

A set of twenty-eight 5 ml vials were charged with 0.25 mmol each of the following Grignards (Table 1) and 1.0 ml solution of 3 (0.1 mmol) in THF. The reactions were shaken overnight, and solvent was removed in vacuo. Samples were checked by mass spectroscopy (Atmospheric Pressure Chemical Ionization) for the presence of the expected product. In all cases, the product was observed.

TABLE 1 m/e + 1 m/e + 1 Example Grignard Concentration Formula expected found 11 p-CH₃—C₆H₄MgBr 1.0M/Ether C₂₄H₃₀P₂ 381.18 381.27 12 p-Cl—C₆H₄MgBr 1.0M/Ether C₂₂H₂₄P₂Cl₂ 421.07 421.19 13 p-(CH₃)₃C—C₆H₄MgBr 2.0M/Ether C₃₀H₄₂P₂ 465.28 465.3 14 H—C≡C—MgBr 0.5M/THF C₁₄H₁₈P₂ 249.08 249.15 15 CH₃C≡CMgBr 0.5M/THF C₁₆H₂₂P₂ 277.11 277.2 16 p-F—C₆H₄MgBr 2.0M/Ether C₂₂H₂₄P₂F₂ 289.13 389.23 17 C₆H₅C≡CMgBr 1.0M/THF C₂₆H₂₆P₂ 401.15 401.27 18 CH₂═CHMgBr 1.0M/THF C₁₄H₂₂P₂ 253.12 253.17 19 cyclopentylMgBr 2.0M/Ether C₂₀H₃₄P₂ 337.21 337.31 20 CH₃(CH₂)₉MgBr 1.0M/Ether C₃₀H₅₈P₂ 481.40 481.57 21 4-Fluoro-3-CH₃—C₆H₃MgBr 1.0M/THF C₂₄H₂₈P₂F₂ 417.16 417.27 22 3,4-difluoro-C₆H₃MgBr 0.5M/THF C₂₂H₂₂P₂F₄ 425.11 425.23 23 p-CH₃(CH₂)₃C₆H₄MgBr 0.5M/THF C₃₀H₄₂P₂ 465.28 465.19 24 3-fluoro-2-methyl-C₆H₃MgBr 0.5M/THF C₂₄H₂₈P₂F₂ 417.16 417.28 25 2-naphthylMgBr 0.25M/THF C₃₀H₃₀P₂ 453.18 453.31 26 p-CH₃S—C₆H₄MgBr 0.5M/THF C₂₄H₃₀P₂S₂ 445.13 445.25 27 3-methoxy-C₆H₄MgBr 0.5M/THF C₂₄H₃₀P₂O₂ 413.17 413.34 28 3-fluoro-4-methyl-C₆H₃MgBr 0.5M/THF C₂₄H₂₈P₂F₂ 417.16 417.3 29 2-methoxy-C₆H₄MgBr 0.5M/THF C₂₄H₃₀P₂O₂ 413.17 413.27 30 4-methoxy-C₆H₄MgBr 0.5M/THF C₂₄H₃₀P₂O₂ 413.17 413.32 31 C₆H₅—O—C₆H₄MgBr 0.5M/THF C₃₄H₃₄P₂O₂ 537.20 537.67 32 p-(CH₃)₂NC₆H₄MgBr 0.5M/THF C₂₆H₃₆P₂N₂ 439.23 439.37 33 2,4-difluoro-C₆H₃MgBr 0.5M/THF C₂₂H₂₂P₂F₄ 425.11 425.24 34 2,4,6-trimethyl-C₆H₂MgBr 1.0M/THF C₂₈H₃₈P₂ 437.24 437.41 35 H₂C═C(CH₃)MgBr 0.5M/THF C₁₆H₂₆P₂ 281.15 281.21 38 CH₂═CHCH₂MgCl 1.0M/Ether C₁₆H₂₆P₂ 281.15 281.23 39 (CH₃)₃SiCH₂MgCl 1.0M/Ether C₁₈H₃₈P₂Si₂ 373.20 373.31 40 R,,,,,,,T 0.5M/THF C₂₂H₃₈P₂O₄ 429.22 429.29 O(CH₂)₃O—CH(CH₂)₂MgBr

Example 41

A flask was charged with 4.00 g (14.9 mmol) of [2-(tetramethylphospholyl)ethyl]dichlorophosphine and ca. 30 mL of tetrahydrofuran and was cooled to −30° C. To this was added dropwise 15 mL of a 1.0 M solution of lithium aluminum hydride in diethyl ether. After warming to room temperature, tetrahydrofuran was removed in vacuo, and the product was extracted with hexane and filtered. Removal of hexane in vacuo produced the oily compound [2-(tetramethylphosphoyl)ethyl]phosphine. ³¹P NMR (122 MHz, tetrahydrofuran-d₈): δ17 (s), −128 (t, J_((P-H))=190 Hz). This crude product was not purified further. In another flask, 1.30 g of this product (6.49 mmol) was dissolved in 80 mL of tetrahydrofuran, and 5.1 mL of 1.6 M n-butyllithium (8.2 mmol) was added to the flask at room temperature and this was stirred for one hour. To this was added dropwise 1.50 g of 2,7-dimethyl-(R,R)-3,6-decadiylsulfate dissolved in 8 mL of THF. This was stirred for 1.5 h at room temperate. Then, 5.1 mL of 1.6 M n-butyllithium (8.2 mmol) was added to the flask at room temperature and this was stirred for one hour. The reaction mixture was quenched with 3 mL of methanol, and the solvent was removed in vacuo. The product was extracted with 150 mL of pentane, and was filtered. Removal of pentane in vacuo yielded 1.74 g of [2-(2-tetramethylphospholyl)ethyl]-[(R,R)-2,7-dimethyl-3,6-decadiyl]phosphine which was purified by oil sublimation (160° C., ca. 1 torr). ³¹P{¹H} NMR (122 MHz, C₆D₆): δ18 (s), −9 (s).

Example 42

Olefin/Carbon Monoxide Copolymerization Using Diphosphole Coordinated Palladium Catalysts

Synthesis of [1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMeCl

The solution of 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane (1.538 g, 5.019 mmol) and (COD)PdMeCl(1.267 g, 4.780 mmol) in 60 mL CH₂Cl₂ was allowed to stir for 1.5 hr at RT. The mixture was filtered. The filtrate was concentrated to ca. 10 mL, followed by addition of 160 mL pentane. The solid was filtered, washed with 3×10 mL pentane and dried in vacuo. Milky white product (2.128 g, 96%) was obtained. ¹H NMR(CD₂Cl₂): δ0.27(dd, 3H, Pd—CH₃); 1.80-2.14 (m, 28H, overlapped ligand CH₂'s and CH₃'s). ³¹P NMR(CD₂Cl₂): δ59.63, 73.55 (1P each).

Example 43

Synthesis of {[1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMe(CH₃CN)}SbF₆

To a −30° C. solution of [1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMeCl (1.47 g, 3.17 mmol) and CH₃CN (1.30 g, 31.7 mmol) in 50 mL CH₂Cl₂ was added AgSbF₆ (1.090 g, 3.17 mmol). This was allowed to warm up slowly to RT and stir at RT for 30 min. The mixture was filtered. The filtrate was concentrated to ca. 5 mL. To the concentrated solution was added 80 mL pentane. The solid was filtered, washed with 3×10 mL pentane and dried in vacuo. Yellow solid (2.172 g, 97%) was obtained. ¹H NMR(CD₂Cl₂): δ0.29(dd, 3H, Pd—CH₃); 1.80-2.20 (m, 28H, overlapped ligand CH₂'s and CH₃'s); 2.24(s, 3H CH₃CN). ³¹P NMR(CD₂Cl₂): δ60.62, 73.32(d, J=18.0 Hz, 1P each).

Example 44

Synthesis of [1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine]PdMeCl

The solution of 1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine (0.341 g, 1.01 mmol) and (COD)PdMeCl (0.224 g, 0.845 mmol) in 20 mL CH₂Cl₂ was allowed to stir for 1.5 hr at RT. The mixture was filtered. The filtrate was concentrated to ca. 5 mL, followed by addition of 75 mL pentane. The solid was filtered, washed with 3×5 mL pentane and dried in vacuo. Red brown product (0.253 g, 61%) was obtained. ¹H NMR(CD₂Cl₂): δ0.25 (dd, 3H, Pd—CH₃); 1.98 (s, 12H, 3,4-CH₃'s); 2.01 (dd, 12H, 2,5-CH₃'s); 2.56 (d, J=8.4 Hz, 3H, N—CH₃); 2.64 (d, J=10.2 Hz, 3H, N—CH′₃). ³¹P NMR(CD₂Cl₂): δ115.80 (d, J=30.3 Hz, 1P); 127.40 (d, J=28.9 Hz, 1P).

Example 45

Synthesis of {[1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine]PdMe(CH₃CN)}SbF₆

To a −30° C. solution of [1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine]PdMeCl (0.20 g, 0.406 mmol) and CH₃CN (0.17 g, 4.15 mmol) in 20 mL CH₂Cl₂ was added AgSbF₆ (0.1394 g, 0.406 mmol). This was allowed to warm up slowly to RT and stir at RT for 40 min. The mixture was filtered through Celite® filteration aid. The filtrate was concentrated to ca. 5 mL. To the concentrated solution was added 75 mL pentane. The solid was filtered, washed with 2×5 mL pentane and dried in vacuo. Light brown solid (0.23 g, 77%) was obtained. ¹H NMR(CD₂Cl₂): δ0.27 (dd, 3H, Pd—CH₃); 1.87 (s, 12H, 3,4-CH₃'s); 1.88 (dd, 12H, 2,5-CH₃'s); 2.26 (s, 3H CH₃CN); 2.57 (d, J=8.7 Hz, 3H, N—CH₃); 2.67 (d, J=11.1 Hz, 3H, N—CH′₃). ³¹P NMR(CD₂Cl₂): δ115.58 (d, J=28.5 Hz, 1P); 125.48 (d, J=30.3 Hz, 1P).

Polymerizations

Reactions were done by using either well-defined palladium catalysts such as [(diphosphole)PdMe(CH₃CN)]SbF₆ or catalysts generated in situ by mixing the diphosphole ligand with the palladium salts such as [Pd(CH₃CN)₄](BF₄)₂ or Pd(OAc)₂. Adding strong acid such as p-toluenesulfonic acid is important when Pd(OAc)₂ is used as the catalyst precursor. Adding excess of benzoquinone as the oxidant in general helps the copolymer yield. The copolymerization works in common organic solvents such as CH₂Cl₂, chlorobenzene and methanol. The synthesis of the organometallic complexes were carried out in a nitrogen drybox. Catalyst screening was more conveniently done in multishaker tubes. When using shaker tubes for ligand and catalyst scouting (Table 2), 25 mL-sized tubes were used. Ligand, catalyst precursor (or single-component catalyst), oxidant (sometimes also p-CH₃C₆H₄SO₃H.H₂O acid) and 5 mL of specified solvent(s) were mixed in the shaker tubes. After purging with nitrogen, these tubes were pressured up with ethylene/CO (1:1) mixed gas and was shaken at 60° C. under ethylene/CO pressure for 18 hr.

Example 46

High Pressure Slurry ECO Copolymerization (100° C., 900 psi) {[1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMe(CH₃CN)}SbF₆ (1.00 g, 1.42 mmole), benzoquinone (3.07 g, 28.4 mmole) and 1460 mL methanol were charged into an one gallon autoclave. The reactor was then charged with mixed ethylene/carbon monoxide gas (1:1) and the temperature was raised up to 100° C. The mixture was allowed to stir at 100° C. under 900 psi of E/CO mixed gas for 6 hr. The reaction was exothermic(cooling coil was used to control the temperature by using water as coolant). Upon cooling, the polymer/methanol mixture was transferred to a blender and was blended to powders. The powdery polymer was then filtered, washed with methanol repeatedly and dried in vacuo at 100° C. for 3 days. White powdery polymer (356 g) was obtained. Based on ¹H and ¹³C NMR, the polymer is perfectly alternating ethylene/CO copolymer. The copolymer exhibited a m.p. of 250° C. based on DSC. GPC (HFIP, polyethylene terephthalate standard): Mw=236,000; Mn=46,800; Mw/Mn=5.0.

Example 47

Slurry ECO Copolymerization (60° C., 700 psi)

{[1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMe(CH₃CN)}SbF₆ (0.60 g, 0.852 mmole), benzoquinone (4.6 g, 42.6 mmole), 1000 mL methanol and 500 mL toluene were charged into an one gallon autoclave. The reactor was then charged with mixed ethylene/carbon monoxide gas (1:1) and the temperature was raised up to 60° C. The mixture was allowed to stir at 60° C. under 700 psi of ECO mixed gas for 6 hr. The reaction was exothermic (cooling coil was used to control the temperature by using water as coolant). Upon cooling, the polymer/methanol mixture was transferred to a blender and was blended to powders. The powdery polymer was then filtered, washed with methanol repeatedly and dried in vacuo at 100° C. for one day. White powdery polymer (243 g) was obtained. Based on ¹H and ¹³C NMR, the polymer is perfectly alternating ethylene/CO copolymer. The copolymer exhibited a m.p. of 242° C. based on DSC. GPC (HFIP, polyethylene terephthalate standard): Mw=149,000; Mn=63,000; Mw/Mn=2.4.

TABLE 1 Shaker tube experiments for Ethylene/CO copolymerization Catalyst or Benzo- E/CO Ligand precursor quinone Acid Pressure Copolymer m.p Ex. (mg) (mg) (mg) (mg) Solvent (psi) Mw/Mn Yield (g) (° C.) 48 0 C-1(4.7) 14.4 0 CH₃OH 708 na 8.5 na 49 0 C-1(42) 0 0 CH₃OH 880 na 23.3 na 50 L-1 Pd(OAc)₂ 130 228 CH₃OH/ 800 na 0.5 na (22) (12.5) toluene 2:1 51 0 C-1(2.0) 6.3 0 CH₃OH 885 381,000/ 1.53 253 151,000 52 0 C-2(29.4) 89.6 0 CH₃OH 885 509,000/ 5.0 245 218,000 53 L-2 P-1(5.7) 27.6 0 CH₃OH 600 707,000/ 11.8 na (5.5) 312,000 L-1 = 1,2-bis(2,3,4,5-tetramethylphospholyl)ethane L-2 = 1,3-bis(2,3,4,5-tetramethylphospholyl)propane C-1 = {[1,2-bis(2,3,4,5-tetramethylphospholyl)ethane]PdMe(CH₃CN)}SbF₆ C-2 = {[1,2-bis(2,3,4,5-tetramethylphospholyl)-1,2-dimethylhydrazine]PdMe(CH₃CN)}SbF₆ P-1 = [Pd(CH₃CN)₄](BF₄)₂

Example 54

ATRP of MMA Using Cu(I)-diphosphole Complex as Catalyst

MMA was passed through a basic alumina column to remove inhibitor, then degassed by freeze-thaw cycle three times. 10 mg of CuCl and 62 mg of 1,2-bis(2,3,4,5-tetramethylphospholyl) ethane were put into 5.0 mL of degassed toluene. 5.0 mL of purified MMA and 66 μL of 2,2′-dichloroacetophenone were added into the above catalyst solution. The solution was mixed well in a Schlenck flask and the flask was sealed under nitrogen and then immersed in an oil bath set at 80° C. Polymerization proceeded at 80° C. with string for 16 hrs. After polymerization was stopped, the solution was diluted with more toluene and then polymer was precipitated into methanol. Polymer solid was collected by filtration, washed with methanol, and dried under vacuum. 0.35 g polymer was obtained (7.5% conversion of MMA). The polymer was analyzed by GPC with THF as eluent and PMMA as standard. The number average molecular weight (M_(n)) was 20200 and M_(w)/M_(n) was 1.32. 

We claim:
 1. A compound of the formula

wherein R₁, R₂, R₃, and R₄ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; R₅ and R₆ are independently selected from the group consisting of hydrogen, hydrocarbyl, substituted hydrocarbyl, Cl, Br, I, hydroxyl, alkoxy, thiol, alkylthio, amino, alkylamino, and dialkylamino; R₂ and R₃ together and R₅ and R₆ together can optionally form a ring; A is a divalent group consisting of optionally-substituted chains of from 1 to 12 linear, branched, or cyclic carbons, optionally containing one or more heteroatoms or organometallic groups in the chain, and —N(R₇)—N(R₈)—; and R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl; with the proviso that R₅ and R₆ together cannot form a phosphole ring, and when A is an aryl group, R₁ and R₄ cannot both be hydrogen.
 2. The compound of claim 1 where A is selected from the group consisting of a carbon chain of 1-3 carbons and —N(R₇)—N(R₈)—, wherein R₇ and R₈ are independently selected from the group consisting of hydrogen, hydrocarbyl, and substituted hydrocarbyl.
 3. The compound of claim 2 wherein R₁, R₂, R₃, and R₄ are alkyl groups.
 4. The compound of claim 3 wherein R₅ and R₆ are selected from the group consisting of hydrocarbyl, substituted hydrocarbyl, and Cl.
 5. The compound of claim 4 that is 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-dichlorophosphinoethane-1,2-dimethylhydrazine; [2-(tetramethylphospholyl)ethyl]-[(R,R)-2,7-dimethyl-3,6-decadiyl]phosphine; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-chlorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-tert-butylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-diethynylphosphinoethane, 1-(2,3,4,5-tetramethylphospholyl)-2-di-(n-propynyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-fluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(phenylethynyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-divinylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-dicyclopentylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(n-decyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-fluoro-3-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3,4-difluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-butylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-fluoro-2-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2-naphthyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methylthiophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-methoxyphenyl)phosphinoethane, 1-(2,3,4,5-tetramethylphospholyl)-2-di-(3-fluoro-4-methylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2-methoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-methoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(4-phenoxyphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-[4-(dimethylamino)phenyl]phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2,4-difluorophenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-(2,4,6-trimethylphenyl)phosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-isopropenylphosphinoethane; 1-(2,3,4,5-tetramethylphospholyl)-2-diallylphosphinoetane; 1-(2,3,4,5-tetramethylphospholyl)-2-di-trimethylsilylmethylphosphinoethane; and 1-(2,3,4,5-tetramethylphospholyl)-2-di-[2-[1,3]dioxan-2-yl-ethyl]phosphinoethane. 